The Mars Exploration Rover (MER) mission roves back into the exploration spotlight this month as Opportunity arrives at the rim of Endeavour Crater, a destination that wasn’t even an impossible dream when the rover landed back in January 2004.

The robot field geologist completed what turned out to be a 21.5-kilometer (13.35-mile) journey from Victoria Crater on August 9th when it crossed the geologic boundary from the plains of Meridiani Planum into Spirit Point and the rock-strewn rim of Endeavour Crater, officially reaching its long-awaited, much-anticipated destination after 1047 Martian days or nearly three Earth years of roving.

“It's just amazing to be here after setting out almost three years ago,” Steve Squyres told the MER Update earlier today. “To tell the truth, when we departed for Endeavour, I wasn't confident that we'd make it. But I wanted to pick a goal that was worthy of this project and this rover, and Endeavour was the obvious choice. Now we've made it, and it feels like a new mission all over again.”

Cape TribulationOpportunity took this image of the Tribulation range with her panoramic camera (Pancam) just before crossing the geologic boundary and pulling into Spirit Point earlier this month. After nearly three Earth years on the road, the rover officially completed the journey from Victoria Crater to Endeavour Crater on Aug. 9, 2011. Orbital data acquired from CRISM onboard the Mars Reconnaissance Orbiter indicates there are deposits of phyllosilicates to be found around Endeavour and the Motherlode is in these hills. Credit: NASA / JPL-Caltech / Cornell / colorization by Stuart Atkinson

Estimated to be about 22 kilometers (14 miles) in diameter, Endeavour Crater is a big deal not just because it’s the biggest hole in the ground the rover is likely to have the chance to study, but because of the evidence of a past environment that is harbored there. Since arriving, Opportunity has begun digging deeper into Martian history, back to the formative wet and warm Noachian Period, a time when life could have emerged on the planet.

The signature for phyllosilicates, more specifically clay minerals that form in a pH neutral water were detected in the area by an instrument onboard the Mars Reconnaissance Orbiter, and now the rover is ground-truthing that signal. Finding the evidence for phyllosilicates would unequivocally point to the potential for life, at least a possible past habitat in which life could have emerged. And it would deliver what many will consider the mission’s greatest scientific achievement.

Now, as August falls to September, Opportunity is heading for the phyllosilicates at Cape York. Since NASA-JPL scheduled a press teleconference for tomorrow, September 1, 2011, to cover Opportunity’s Endeavour Crater arrival, the MER Update for August 2011 will be posted tomorrow to include comments and news from the press briefing. Please check back tomorrow evening PDT for a full report.

Spirit Point in 3-DThe 3-D view of where Opportunity first arrived in the rim zone of Endeavour Crater, an impact crater about 22 kilometers (14 miles) in diameter. The team dubbed the location of the rover's arrival Spirit Point, as a tribute to Opportunity's rover twin, which stopped communicating in March 2010 after more than six years of work on Mars. The view here encompasses nearly a full circle, from northeast at the left, around to straight north at the right. The small crater on Endeavour's rim near the left edge of the scene has been nicknamed Odyssey, as a tribute to the Mars Odyssey orbiter, which has served as the communications relay for nearly all of the data sent by both rovers since they landed on Mars in January 2004.View with red-blue glasses,red lens on the left.Credit: NASA / JPL-Caltech